2 Days and two pre-combustion chambers out. I started out with a few tools and by the end of the day I had a big mess. The next two are going to be more trouble as they stripped out where the removing tool fits.  Bill

Not going back to read and remember what all you have going, but if you can get replacement for your chambers weld a bolt into the top. When it cools generally things come out easier as you have heated the rust and as it shrinks the rust lets go.

Thanks, That was the final solution for getting them out. Bill

That is good news. I have seen videos of Squatch using a 40 ft cheater bar    to get some loose but does an impact work for getting them out?  Or will an impact "round" out the internal edges like what happened to these?  On a lot of farm machinery I have found the impact (Plus Kroil) does a better job than a long cheater bar.

this could be probably another thread but it's good...for stuck/ stubborn fasteners/threads...my list...

1) heat of any kind, welding washers, nuts, etc...torch...all good....be safe doing so...
2) penetrating oils and time...
3) impact guns of some kind...something that delivers a shock etc...
4) usually any kind of movement is good...keep working...

I hope to put the engine together this winter and will post pictures. This is the punch card that was on  the box of the NOS 3 3/4" piston kit. Bill

Glad to see your'e still out here perfecting your collection of goodies. It will be another gem when you finish it.
I wonder if anyone here knows how that punch card process system for parts from manufacture to warehouse, to distribution worked.
Up at the top of this thread, guys mentioned frozen, rusted fasteners. Has anyone purchased one of the new fangled "induction" tools for heating? Curious if there is one out there worth spending $ on. A tool to many of us only needs to be used once to justify ownership!
Keep us posted Bill. Thx, JM